>>21308549He bonded to alcohol because he hasn't bonded with people. Talk to him, hang out with him, even if he's drinking or he's not.
Have him start taking Acetyl L-Carnitine once a day. Ask him to still be there for you in 5 years. Drinking like that he's gonna die young, but his life can and will get better. That's what he needs to hear.
Connection, medication, hope.